JP2851124B2 - Multiplex transmission system - Google Patents

Multiplex transmission system

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Publication number
JP2851124B2
JP2851124B2 JP2113751A JP11375190A JP2851124B2 JP 2851124 B2 JP2851124 B2 JP 2851124B2 JP 2113751 A JP2113751 A JP 2113751A JP 11375190 A JP11375190 A JP 11375190A JP 2851124 B2 JP2851124 B2 JP 2851124B2
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Prior art keywords
transmission line
multiplex
transmission
signal transmission
signal
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JPH0410828A (en
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圭 井上
恭介 橋本
敦彦 鈴木
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古河電気工業株式会社
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00Data switching networks
    • H04L12/28Data switching networks characterised by path configuration, e.g. local area networks [LAN], wide area networks [WAN]
    • H04L12/40Bus networks
    • H04L12/40169Flexible bus arrangements
    • H04L12/40176Flexible bus arrangements involving redundancy
    • H04L12/40182Flexible bus arrangements involving redundancy by using a plurality of communication lines
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00Data switching networks
    • H04L12/28Data switching networks characterised by path configuration, e.g. local area networks [LAN], wide area networks [WAN]
    • H04L12/40Bus networks
    • H04L12/40006Architecture of a communication node
    • H04L12/40013Details regarding a bus controller
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00Data switching networks
    • H04L12/28Data switching networks characterised by path configuration, e.g. local area networks [LAN], wide area networks [WAN]
    • H04L12/40Bus networks
    • H04L12/407Bus networks with decentralised control
    • H04L12/413Bus networks with decentralised control with random access, e.g. carrier-sense multiple-access with collision detection (CSMA-CD)
    • H04L12/4135Bus networks with decentralised control with random access, e.g. carrier-sense multiple-access with collision detection (CSMA-CD) using bit-wise arbitration
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/02Details ; Arrangements for supplying electrical power along data transmission lines
    • H04L25/14Channel dividing arrangements in which a single bit stream is divided between several baseband channels and reassembled at the receiver
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00Data switching networks
    • H04L12/28Data switching networks characterised by path configuration, e.g. local area networks [LAN], wide area networks [WAN]
    • H04L12/40Bus networks
    • H04L2012/40208Bus networks characterized by the use of a particular bus standard
    • H04L2012/40215Controller Area Network CAN

Description

【発明の詳細な説明】 (産業上の利用分野) 本発明は、共通の伝送線に接続された多重ノード間で、データの伝送を行う多重伝送方式に関する。 BACKGROUND OF THE INVENTION (FIELD OF THE INVENTION) The present invention, among multiple nodes connected to a common transmission line, to a multiplex transmission method for transmitting data.

(従来の技術) 従来、この種の多重伝送方式には、CSMA/CD(Carrier (Prior Art) Conventionally, a multiplex transmission method of this kind, CSMA / CD (Carrier
Sence Multiple Acess/Collision Detection)と、AMP Sence Multiple Acess / Collision Detection) and, AMP
(Arbitration on Message Priority)とを用いたLAN (Arbitration on Message Priority) and the LAN using the
(Local Area Network)の伝送方式がある。 There are transmission method (Local Area Network). 例えばその代表的なものに自動車内のデータ伝送に用いられるCAN For example CAN used for data transmission in a motor vehicle in its typical
(Controller Area Network)等がある。 There is a (Controller Area Network) and the like.

第10図は、その従来例の構成ブロック図であり、2つの伝送線A,Bの両端に終端抵抗R E ,R Eを接続すると共に、 FIG. 10, the conventional example is a configuration block diagram of two transmission lines A, termination resistor R E to both ends of B, with connecting R E,
上記伝送線A、Bに並列に多重ノード11〜13が接続されている。 It said transmission line A, multiplex nodes 11 to 13 are connected in parallel to the B. 多重ノード11〜13は、それぞれ同一の構成なので、説明の都合上、多重ノード11について説明する。 Multiple nodes 11 to 13, since each of the same construction, for convenience of description, a multi-node 11.

多重ノード11は、通信制御装置21と、通信制御装置21 Multiple node 11, a communication control unit 21, communication controller 21
より送信信号を受け取り、伝送線A,Bに送信する送信回路と、伝送線A、Bより信号を受信し、通信制御装置21 It receives more transmission signals, received a transmission circuit for transmitting the transmission line A, to B, the transmission line A, the signal from B, the communication control device 21
に送出する受信回路とからなっている。 It consists a receiving circuit for sending to.

受信回路は、抵抗R 3 〜R 9からなり、伝送線A,Bより受信した信号を通信制御装置21のコンパレータ21aに出力し、上記コンパレータ21aに適当なスレッシュホルド電圧を与えることにより、伝送信号の振幅を許容できるまで小さくして、受信回路のコモンモード入力電圧範囲を広げ、ノイズによる影響を受けづらくしている。 Receiving circuit, a resistor R 3 to R 9, the transmission line A, and outputs a signal received from the B to the comparator 21a of the communication control device 21, by providing the appropriate Suresshuhorudo voltage to the comparator 21a, the transmission signal and reduced to an acceptable amplitude of the spread common-mode input voltage range of the receiving circuit, and hardly affected by noise.

送信回路は、電界効果トランジスタ(FET)22,23と、 Transmission circuit includes a field effect transistor (FET) 22, 23,
ダイオードD 1 ,D 2と抵抗R 1 ,R 2からなる回路で構成されており、FET22はダイオードD 1と抵抗R 1を介して伝送線A Diodes D 1, D 2 and resistors R 1, is constituted by a circuit consisting of R 2, FET 22 is diode D 1 and a resistor R 1 transmission line A through the
に接続し、FET23はダイオードD 2と抵抗R 2を介して伝送線Bに接続している。 Connected to, FET 23 is connected to the transmission line B via the diode D 2 and resistor R 2.

従って、多重ノード11がパッシブ時、すなわちCSMA/C Therefore, when multiple nodes 11 passive, i.e. CSMA / C
D+AMPの伝送方式において、劣性ビットを出力する時は、FET22,23は共にオフで、伝送線Aと伝送線Bの間には、電位差が生ぜずハイインピータンス状態になる。 In transmission scheme D + AMP, when outputting recessive bits, FET22,23 are both off, while the transmission line B and the transmission line A will Haiinpi over chest state not occur potential difference. また、多重ノード11がドミナント時、すなわち優性ビットを出力する時は、FET22,23は共にオンであり、伝送線A Further, when multiple nodes 11 dominant, that is, when outputting a dominant bit, FET22,23 are both ON, the transmission line A
に電流を供給し、伝送線Bからの電流を取り込む。 Supplying current to, taking the current from the transmission line B. このため、ドミナント時には伝送線A,Bの間には電位が生じ、伝送線A、Bに接続されている受信回路は電位差を検知し、コンパレータ21aを反転させ、ドミナントを検知するものがあった。 Therefore, the dominant time caused a potential between the transmission line A, B, receiving circuits connected transmission line A, and B detects the potential difference, the comparator 21a is reversed, there is one that detects a dominant .

(発明が解決しようとする課題) ところが、上記伝送方式では、例えば伝送線の一方が断線又は短絡する等の故障が発生した場合、各伝送線間の電位が変化してしまい、伝送線の全ての多重ノード間のデータ伝送ができなくなるという問題点があった。 (Problems to be Solved) However, in the above transmission method, for example, if one of the transmission line fault such as disconnection or short circuit occurs, the potential between the transmission line would change, all the transmission lines there a problem that the data transmission becomes impossible between the multiple nodes.

本発明は、上記問題点に鑑みなされたものであって、 The present invention was made in view of the above problems,
伝送線上の故障が生じても各多重ノード間でデータ伝送を効率的に行うことができる多重伝送方式を提供することを目的とする。 Even if the failure of the transmission line occurs and to provide a multiplex transmission method capable of transmitting data efficiently among multiple nodes.

(課題を解決するための手段) 上記目的を達成するために、本発明では、共通の信号伝送線を介して相互に接続された少なくとも2つの多重ノードを有し、当該各多重ノードはいずれかの多重ノードの送信要求に応じて所定の送信データを送信する多重伝送方式において、前記信号伝送線は少なくとも3つの信号伝送線からなり、前記各多重ノードは該信号伝送線のうち少なくとも1つの信号伝送線の電圧を検知し、該電圧値に応じて各信号伝送線の状態を特定し、かつ、少なくとも1つの多重ノードは前記各多重ノードと通信して故障を検知した際には、前記信号伝送線の電圧を変化させて前記各信号伝送線の状態を変化させ、各多重ノード間のデータ伝送を行う多重伝送方式が提供される。 To achieve (solutions for the problem) above object, the present invention has at least two multiple nodes are connected to one another via a common signal transmission line, either the respective multiplex nodes in the multiplex transmission system for transmitting a predetermined transmission data in response to the transmission request of the multiple nodes, the signal transmission line comprises at least three signal transmission lines, at least one signal of said each multiplex node the signal transmission line it detects the voltage of the transmission line, in accordance with the voltage value to identify the state of each signal transmission line, and at least one multiple nodes upon detecting a failure in communication with each of the multiplex nodes, the signal changing the voltage of the transmission line by changing the state of the respective signal transmission lines, multiplex transmission method for transmitting data between the multiplex nodes are provided.

(作用) 多重ノードのうち、少なくとも1つの多重ノードは、 (Action) of the multi-node, at least one multiple nodes,
信号伝送線の故障を検知すると、信号伝送線の電圧を変化させることによって各信号伝送線の状態をデータ伝送可能な状態に変化させる。 Upon detecting the failure of the signal transmission line, it is changed to a state enabling data transmission state of each signal transmission line by changing the voltage of the signal transmission line.

従って、各多重ノードは、信号伝送線の断線や短絡による故障が生じても、信号伝送線の間には所定の電位が生じ、各多重ノード間のデータ伝送が可能になる。 Thus, each multiplex node, even if failure due disconnection and short circuit of the signal transmission line, between the signal transmission line occurs a predetermined potential, allowing data transmission between multiplex nodes.

(実施例) 以下、本発明の実施例を第1図乃至第9図の図面に基づき詳細に説明する。 (Example) Hereinafter, an embodiment of the present invention in detail with reference to the accompanying drawings in Figure 1 to Figure 9.

第1図は、本発明に係る多重伝送方式の構成を示す構成ブロック図である。 Figure 1 is a block diagram showing a configuration of a multiplex transmission method according to the present invention. 図において、各多重ノード30,40, In the figure, each multiplex node 30 and 40,
50,60は、それぞれ3本の伝送線A、B、Cに接続されており、各多重ノード間でのデータ信号の伝送を行っている。 50 and 60, the transmission line A of each of the present 3, B, are connected to C, and performing the transmission of data signals between the multiple nodes. 各多重ノードのうち、伝送線の終端部以外に接続されている多重ノード30,40は、それぞれ同一の構成ブロックになっているので、ここでは説明の都合上代表して多重ノード30の構成を説明する。 Among the multi-node, multi-node 30 and 40 that are connected to the other end of the transmission line, since each has the same building blocks, the structure of the multiplex nodes 30 on behalf convenience of description here explain.

多重ノード30は、通信処理制御を行う通信制御装置31 Multiple node 30, the communication control unit performs communication processing control 31
と、通信制御装置31から送信信号を受け取り、伝送線に送出する送信制御回路32と、伝送線から取り込んだ受信信号を通信制御装置31に与える受信制御回路33と、上記信号伝送線のうちの1つ、例えば伝送線Cの電圧を検知して伝送線Cの状態を上記通信制御装置31等に知らせる電圧検知回路34とから構成されている。 When receiving the transmission signal from the communication control unit 31, a transmission control circuit 32 to be transmitted to the transmission line, the reception control circuit 33 which provides a received signal taken from the transmission line to the communication control device 31, of the signal transmission line one has the state of the transmission line C, for example, detecting the voltage of the transmission line C is constituted by the voltage detection circuit 34 for informing the above-described communication control device 31 or the like.

また、伝送線の終端部に接続された多重ノード50,60 Also, multiple nodes 50 and 60 connected to the end of the transmission line
は、多重ノード30と同様の機能である通信制御装置51,6 The communication control device is the same function as that of the multi-node 30 51,6
1と、送信制御回路52,62と、受信制御回路53,63と、電圧検知回路54,64とをそれぞれ有すると共に、伝送線A, 1, a transmission control circuit 52 and 62, a reception control circuit 53 and 63, with each having a voltage detection circuit 54 and 64, the transmission lines A,
B,Cの両端に終端抵抗を接続した終端回路54,64が付加されている。 B, termination circuit 54 and 64 which connect a terminator is added to both ends of the C. また、終端部に接続された多重ノード50,60 Also, multiple nodes 50 and 60 connected to the terminal end
のうちの一方、例えば多重ノード50には、伝送線Cに電圧を印加する電圧発生回路56も付加されている。 One of, for example, the multi-node 50 is added the voltage generating circuit 56 for applying a voltage to the transmission line C.

上記各電圧検知回路は、第2図に示すような回路構成になっており、電圧比較回路CM 1 ,CM 2の一方の端子には、伝送線Cの電圧V 0が抵抗R 10とコンデンサC 10とからなるフィルタ回路を介して印加し、他方の端子には、分圧抵抗R 11 〜R 13によって電源電圧V CCを分圧して得た基準電圧V 1 ,V 2が印加しており、伝送線Cの電圧値が上記基準電圧V 1 ,V 2の範囲内かどうか検知している。 Each voltage detection circuit is adapted to circuit configuration as shown in FIG. 2, the one terminal of the voltage comparator circuit CM 1, CM 2, the voltage V 0 which transmission line C is resistor R 10 and capacitor C via a filter circuit consisting of 10 Metropolitan applied to the other terminal, the reference voltage V 1, V 2 of the power supply voltage V CC is obtained by dividing the dividing resistor R 11 to R 13 are applied, voltage value of the transmission line C is detecting whether the range of the reference voltage V 1, V 2. すなわち電圧V 0が基準電圧V 1 ,V 2の範囲内にある場合には、正常状態として出力端子K 1 ,K 2には“0"、“0"がそれぞれ出力され、電圧V 0が基準電圧V 1 ,V 2の範囲を越えた場合、例えば伝送線Aが断線した場合には、異常状態として出力端子K 1 ,K 2には“1"、“0"がそれぞれ出力され、 That is, when the voltage V 0 is within the range of the reference voltage V 1, V 2 is the output terminal K 1, K 2 as a normal state "0", "0" is output, respectively, the voltage V 0 reference If the value exceeds the range of voltages V 1, V 2, for example, when the transmission line a is disconnected, the output terminal K 1, K 2 as an abnormal state "1", "0" is output, respectively,
また電圧V 0が基準電圧V 1 ,V 2の範囲を越えた場合、例えば伝送線B、Cが短絡した場合にも、異常状態として出力端子K 1 ,K 2には“0"、“1"がそれぞれ出力される。 In the case where the voltage V 0 exceeds a range of the reference voltages V 1, V 2, for example, the transmission line B, even if the C is short-circuited, the output terminal K 1, K 2 as an abnormal state "0", "1 "it is output, respectively.

送信制御回路は、第3図に示すように、第8図の従来例と同様、FET35,36と、ダイオードD 1 ,D 2と抵抗R 14 ,R 15 Transmission control circuit, as shown in FIG. 3, similarly to the conventional example of FIG. 8, a FET35,36, diodes D 1, D 2 and resistors R 14, R 15
からなるフィルタ回路とから構成されており、FET35はダイオードD 10と抵抗R 14からなるフィルタ回路を介して伝送線Aに接続し、FET36はダイオードD 11と抵抗R 15からなるフィルタ回路を介して伝送線Bに接続して送信信号を送信している。 Are composed of a filter circuit composed of, FET 35 is connected to the transmission line A through a filter circuit comprising a diode D 10 and the resistor R 14, via a filter circuit FET36 is a diode D 11 and a resistor R 15 and connected to the transmission line B is transmitting a transmission signal.

受信制御回路では、第4図に示すように、伝送線A,B, In the reception control circuit, as shown in FIG. 4, the transmission lines A, B,
Cには、抵抗R 16 ,R 17 ,R 18を介して電源電圧1/2V CCが印加している。 The C, supply voltage 1 / 2V CC through a resistor R 16, R 17, R 18 are applied. 伝送線A,B,Cの一端と、電圧比較回路CM 3の入力端子とは、図に示すスイッチ端子S 1 〜S 4とによって接続している。 Transmission lines A, B, and one end and C, the input terminal of the voltage comparator circuit CM 3 are connected by the switch terminals S 1 to S 4 shown in FIG. 上記スイッチ素子S 1 〜S 4は、通信制御装置によってオン/オフ制御されており、通信制御装置は電圧検知回路のK 1 ,K 2から入力する信号に応じてスイッチ素子S 1 〜S 4を以下に示す第1表の組合せで、オン/オフ制御している。 The switch element S 1 to S 4 is turned on / off controlled by the communication control device, the communication control device the switching element S 1 to S 4 in accordance with a signal input from the K 1, K 2 of the voltage detection circuit a combination of table 1 below, and on / off control. なお、抵抗R 16 〜R 23は、分圧及びスレッシュホルド電圧設定用の抵抗である。 The resistance R 16 to R 23 is the resistance of the voltage divider and Suresshuhorudo voltage setting.

また、受信制御回路は、K 1 ,K 2が“0"、“0"の正常状態では、伝送線Aを正論理、伝送線Bを負論理により平衡伝送するもの、すなわち伝送線Aは電圧が高い場合にドミナント、伝送線Bは電圧が低い場合にドミナントとして受信するものとする。 The reception control circuit, K 1, K 2 is "0", the normal state of "0", the transmission line A positive logic, which balanced transmission by negative logic transmission line B, that the transmission line A is a voltage dominant if high, the transmission line B is assumed to be received as dominant when the voltage is low. また、K 1 ,K 2が“1"、“0"の異常状態では、伝送線Cを固定電位線、伝送線Bを負論理の不平衡伝送として受信し、K 1 ,K 2が“0"、“1"の異常状態では、伝送線Cを固定電位線、伝送線Aを正論理の不平衡伝送として受信する。 Also, K 1, K 2 is "1", the abnormal state of "0", to receive a transmission line C fixed potential line, the transmission line B as negative logic of the unbalanced transmission, K 1, K 2 is "0 "" in the abnormal state of the 1 ", it receives the transmission line C fixed potential line, the transmission line a of the positive logic as the unbalanced transmission. 伝送状態では、どの状態においても伝送線Cには、伝送波形の高周波成分をほとんど含んでおらず、伝送線Cが外側をとりまく伝送線A、Bを中心とした線を利用することができるため、従来の2芯シールド線と同等で伝送線のコストが上がらない。 The transmission conditions, the transmission line C at any state, does not include most of high-frequency components of the transmit waveform, the transmission line A to the transmission line C is surrounding the outer, it is possible to use a line around the B , it does not increase the cost of the conventional two-core shielded line equal in transmission lines.

終端回路55は、第5図に示すように、伝送線A,Bの両端に接続された抵抗R Eを伝送線CでR E /2に分割し、伝送線Cを抵抗R 24を介してスイッチ素子S 5 ,S 6に接続して構成されている。 Termination circuit 55, as shown in FIG. 5, through a transmission line A, to divide the both ends connected resistors R E and B to R E / 2 in the transmission line C, the resistance R 24 of the transmission line C which are connected to the switching element S 5, S 6. なお、抵抗R 24は、終端抵抗に比べ十分小さい。 The resistor R 24 is sufficiently smaller than the terminating resistor. スイッチ素子S 5は、K 1が“1"のとき、またスイッチ素子S 6は、K 2が“1"のとき、それぞれオンするように構成されている。 Switching element S 5, when the K 1 is "1", also switching element S 6, when the K 2 is "1", and is configured to turn on, respectively. また、終端回路55は、伝送線Cの電圧発生回路56の代わりにもなっており、例えば多重ノード50において、強制的にK 1 ,K 2を“1"、“0"の状態にしたいときには、通信制御装置51の制御によってスイッチ素子S 5をオンにし、また強制的にK 1 ,K 2を“0"、“1"の状態にしたいときには、通信制御装置51の制御によってスイッチ素子S 6をオンにする。 Further, the termination circuit 55 is adapted to place the voltage generating circuit 56 of the transmission line C, for example in a multiplex node 50, forces the K 1, K 2 "1", if you want to state "0" , when to turn on the switching element S 5 under the control of the communication control device 51, also forces the K 1, K 2 "0", like in a state of "1", the switch element S 6 under the control of the communication control device 51 a turn on.

なお、本実施例では、終端回路55と、電圧発生回路56 In this embodiment, a termination circuit 55, the voltage generating circuit 56
が多重ノード50内で共通になっているため、伝送状態を制御する多重ノード50が強制的にK 1 ,K 2を“0"、“1"の状態からK 1 ,K 2を“0"、“0"の状態に変化させる場合、 Since There are common in the multi-node 50, a multi-node 50 which controls the transmission status is forcibly K 1, K 2 "0", "1" to K 1, K 2 from the state of "0" , If you want to change in the state of "0",
電圧発生回路56のみを制御しても、例えば多重ノード60 It is controlled only voltage generation circuit 56, for example, multiple nodes 60
のように、伝送状態を制御せず、かつ、終端回路を有している多重ノードについては、K 1 ,K 2が“0"、“1"の状態を保持してしまうので、伝送線より信号を送出して多重ノード60の電圧検知回路64の出力状態にかかわらず伝送状態を強制的にK 1 ,K 2が“0"、“0"の状態にできるものとする。 As in, without controlling the transmission state, and, for multi-node has a termination circuit, K 1, K 2 is "0", because thereby holding the state of "1", from the transmission line forcibly K 1, K 2 transmission state regardless of the output state of the voltage detection circuit 64 of the multi-node 60 sends out a signal "0", and it can in the state of "0".

次に、多重ノード50による信号線の故障処理の動作を第6図のフローチャートに基づき説明する。 It will now be described based on the operation of the failure processing of the signal lines by multiplexing node 50 in the flow chart of Figure 6. なお、多重ノード50においては、受信制御回路53は第4図に示したスイッチ素子S 1 〜S 4のうち、S 1 ,S 4をオン、S 2 ,S 3をオフにセットし、電圧検知回路54のK 1 ,K 2からの出力は“0"、“0"の正常状態にあるものとする。 Incidentally, in the multiplex node 50, among the switching elements S 1 to S 4 shown in Figure 4 is the reception control circuit 53 sets the S 1, S 4 on and off S 2, S 3, the voltage detection the output from the K 1, K 2 of the circuit 54 is assumed to be a normal state of "0", "0".

まず、通信制御装置51は、各受信多重ノードが正常にフレームを送信できるかどうかにより、送信信号のフレームを受信したときに返送送信が可能かどうか判断する(ステップ101)。 First, the communication control device 51, depending on whether the received multiplex node can successfully send frame, to determine whether it is possible to return transmission when receiving the frame of the transmission signal (step 101).

次に全ての多重ノードと通信可能かどうか、上記同様全ての多重ノードからのACK信号の受信を確認して判断し(ステップ102)、通信が可能の場合には、K 1 ,K 2が“0"、“0"の正常状態を維持して(ステップ103)、再びステップ101の判断を行う。 Then whether it is possible to communicate with all of the multiplex nodes, the same all the reception of the ACK signal from the multiplex node determines to check (step 102), if the communication is enabled, it K 1, K 2 " 0 "," to maintain the normal state of 0 "(step 103), performs again the determination in step 101.

また、ステップ101で送信が不可能な場合、或いはステップ102で全ての多重ノードとの通信が不可能な場合には、受信制御回路53の第4図に示したスイッチ素子S 1 Further, If it is not transmitted in step 101, or when it is impossible to communicate with all of the multiplex nodes in step 102, switching element S 1 shown in FIG. 4 of the reception control circuit 53
〜S 4のうち、S 1 ,S 3をオン、S 2 ,S 4をオフにセットし、次に強制的に終端回路55のスイッチ素子S 5をオンにして、 Of to S 4, the S 1, S 3 ON, and sets off the S 2, S 4, then forced to turn on the switching element S 5 of the termination circuit 55,
K 1 ,K 2を“1"、“0"の状態へ変える(ステップ104)。 The K 1, K 2 "1" , changing to the state of "0" (step 104). このとき伝送線Cの電圧はV 1以上となり、接続されているノードは全てK 1 =1、K 2 =0となる。 Voltage of the transmission line C at this time becomes V 1 or more, connected nodes are all K 1 = 1, K 2 = 0. そして、受信多重ノードとの送信が可能かどうか、ステップ101と同様に判断する(ステップ105)。 Then, whether it is possible to transmit and receive multiple node, similarly determines that step 101 (step 105).

ここで、受信多重ノードとの送信が可能の場合には、 Here, in the case of possible transmission and reception multiplex node,
次に全ての多重ノードと通信可能かどうか、ステップ10 Then whether it is possible to communicate with all of the multiplex nodes, step 10
2と同様に判断し(ステップ106)、通信が可能の場合には、K 1 ,K 2が“1"、“0"の状態を維持して(ステップ10 2 and similarly determined (step 106), if the communication is possible is, K 1, K 2 is to maintain the state of "1", "0" (Step 10
7)、再びステップ105の判断を行う。 7), the re-determination in step 105.

また、ステップ105で送信が不可能な場合、或いはステップ106で全ての多重ノードとの通信が不可能な場合には、受信制御回路53の第4図に示したスイッチ素子S 1 Also, if in step 105 the transmission is impossible, or when it is impossible to communicate with all of the multiplex nodes in step 106, switching element S 1 shown in FIG. 4 of the reception control circuit 53
〜S 4のうち、S 1 ,S 3をオフ、S 2 ,S 4をオンにセットし、次に強制的に終端回路55のスイッチ素子S 5をオフ、S 6をオンに制御して、K 1 ,K 2を“0"、“1"の状態へ変える(ステップ108)。 Of to S 4, the S 1, S 3 off, and set on the S 2, S 4, then forced off the switching element S 5 of the termination circuit 55 controls to turn on the S 6, the K 1, K 2 "0" , changing to the state of "1" (step 108). このとき伝送線Cの電圧はV 2以下となり、接続されているノードは全てK 1 =0、K 2 =1となる。 Voltage of the transmission line C at this time becomes V 2 less, connected nodes are all K 1 = 0, K 2 = 1. そして、受信多重ノードとの送信が可能かどうか、 Then, whether it is possible to transmit and receive multiple nodes,
ステップ101と同様に判断する(ステップ109)。 Step 101 similarly determines (step 109).

ここで、受信多重ノードとの送信が可能の場合には、 Here, in the case of possible transmission and reception multiplex node,
次に全ての多重ノードと通信可能かどうか、ステップ10 Then whether it is possible to communicate with all of the multiplex nodes, step 10
2と同様に判断し(ステップ110)、通信が可能の場合には、K 1 ,K 2が“0"、“1"の状態を維持して(ステップ11 2 and similarly determined (step 110), if the communication is possible is, K 1, K 2 is to maintain the state of "0", "1" (step 11
1)、再びステップ109の判断を行う。 1), and again it determines in step 109.

また、ステップ109で送信が不可能な場合、或いはステップ110で全ての多重ノードとの通信が不可能な場合には、伝送線の故障以外であると判断して、強制的に終端回路55のスイッチ素子S 5 ,S 6を共にオフに制御して、K Further, If it is not transmitted in step 109, or when it is impossible to communicate with all of the multiplex nodes in step 110, it is determined to be other than failure of the transmission line, the forced termination circuit 55 the switching element S 5, S 6 are both controlled to turn off, K
1 ,K 2を“0"、“0"の状態に戻して(ステップ112)、その他の故障処理のルーチンに動作を移す(ステップ11 1, the K 2 "0", "0 " is returned to the state (step 112), it moves the operation to a routine other failure process (step 11
3)。 3).

これにより、多重ノード50は、K 1 ,K 2が“0"、“0"の正常状態の場合、第7図(a)に示すように、ドミナント時には伝送線A、Bの間には電位が生じ、伝送線A、 Thus, multiple node 50, when the normal state of K 1, K 2 is "0", "0", as shown in FIG. 7 (a), between the transmission lines A, B at the time of dominant potential occurs, transmission lines A,
Bに接続されている受信制御回路53は電位差を検知し、 Reception control circuit 53 connected to the B detects the potential difference,
通信制御装置51はドミナントを検知することができる。 The communication control device 51 can detect the dominant.
また、伝送線の1本が一定電圧に固定された場合、伝送線の1本が断線した場合、任意の伝送線の2本が短絡した場合には、まず受信制御回路53の第4図に示したスイッチ素子S 1 〜S 4のうち、S 1 ,S 3をオン、S 2 ,S 4をオフにセットし、次に強制的に終端回路55のスイッチ素子S 5をオンにして、K 1 ,K 2を“1"、“0"の状態へ変え、この状態で送信可能な時には、第7図(b)に示すように、ドミナント時には伝送線C、Bの間には電位が生じ、伝送線C、Bに接続されている受信制御回路53は電位差を検知し、通信制御装置51はドミナントを検知することができる。 Also, if one transmission line is fixed at a constant voltage, if one transmission line is disconnected, if two arbitrary transmission line is short-circuited, first in Figure 4 of the reception control circuit 53 of switching elements S 1 to S 4 shown, the S 1, S 3 oN, and sets off the S 2, S 4, then forced to turn on the switching element S 5 of the termination circuit 55, K 1, changing to the state of the K 2 "1", "0 ", at the time that can be sent in this state, as shown in FIG. 7 (b), the transmission line C, and the potential between the B occur in dominant when , the transmission line C, the reception control circuit 53 connected to the B detects the potential difference, the communication control device 51 can detect the dominant. なお、この場合、伝送線Aの電位は任意でよい。 In this case, the potential of the transmission line A may be arbitrary. また、上記K 1 ,K 2が“1"、“0"の状態の場合、送信が不可能な時には、受信制御回路53の第4図に示したスイッチ素子S 1 〜S 4のうち、S 1 ,S 3をオフ、S 2 ,S 4をオンにセットし、次に強制的に終端回路55のスイッチ素子S 5をオフ、 Further, the K 1, K 2 is "1", when the state of "0", when the transmission is not possible, of the switching elements S 1 to S 4 shown in Figure 4 of the reception control circuit 53, S 1, S 3 off, is set to turn on S 2, S 4, then forced off the switching element S 5 of the termination circuit 55,
S 6をオンに制御して、K 1 ,K 2を“0"、“1"の状態へ変え、この状態で送信可能な時には、第7図(c)に示すように、ドミナント時には伝送線A、Cの間には電位が生じ、伝送線A,Cに接続されている受信制御回路53は電位差を検知し、通信制御装置51はドミナントを検知することができる。 And controls the S 6 on, changing the state of the K 1, K 2 "0" , "1", at the time that can be sent in this state, as shown in FIG. 7 (c), transmission line dominant when a, the potential is generated between the C, the transmission lines a, the reception control circuit 53 connected to the C detects the potential difference, the communication control device 51 can detect the dominant. なお、この場合、伝送線Bの電位は任意でよい。 In this case, the potential of the transmission line B may be arbitrary.

なお、第8図は、本発明に係る受信制御回路の他の実施例であり、この例では電圧比較回路をCM 4 〜CM 6の3個とし、各電圧比較回路からの出力信号(電位差)をセレクト回路SEに取り込み、ここでK 1 ,K 2からの出力に応じて上記取り込んだ出力信号を選択、すなわちK 1 =K 2 =0 Incidentally, FIG. 8 shows another embodiment of a reception control circuit according to the present invention, the voltage comparison circuit in this example the three CM 4 ~CM 6, the output signals from the voltage comparison circuit (voltage difference) the incorporation to the select circuit SE, selecting an output signal taken above depending where the output from K 1, K 2, i.e. K 1 = K 2 = 0
の時には、セレクト回路SEはCM 4からの出力信号を選択し、K 1 =1の時には、CM 5からの出力信号を選択し、K 2 When the select circuit SE selects the output signal from the CM 4, when K 1 = 1 selects the output signal from the CM 5, K 2
=1の時には、CM 6からの出力信号を選択して通信制御装置に出力するように構成することも可能である。 = Of the time 1, it is also possible to configure so as to output to the communication controller selects the output signal from the CM 6. この場合には、複数のスイッチ素子が不要となり、部品点数を削減することができる。 In this case, a plurality of switching elements is not required, to reduce the number of components.

また、第9図は、本発明に係る多重ノードの他の実施例であり、この例では通信制御装置70が各伝送線の通信可能な状態をK 1 =K 2 =0、K 1 =1、K 2 =1の中から検知できるようにしたもので、K 1 ,K 2の各状態を受信制御回路72に出力して、受信制御回路71内の電圧比較回路からの出力信号(電位差)を選択して、送信制御回路72からの送信が可能な最適な伝送状態を検出することが可能となる。 Further, FIG. 9 shows another embodiment of a multi-node according to the present invention, a communicable state of the transmission line communication controller 70 in this example K 1 = K 2 = 0, K 1 = 1 , which was to be able to detect from the K 2 = 1, K 1, and outputs the respective states of K 2 to the reception control circuit 72, the output signal from the voltage comparator circuit of the reception control circuit 71 (potential difference) select, it is possible to detect the optimum transmission state that can be transmitted from the transmission control circuit 72. この場合には、電圧検知回路が不要となり、部品点数を削減することができると共に、上記電圧検知回路を備えたノードと、備えていないノードとを共存させることが可能となる。 In this case, the voltage detection circuit becomes unnecessary, it is possible to reduce the number of components, and nodes with the voltage detection circuit, it is possible to coexist with nodes that do not have.

従って、本実施例では、各多重ノードは、伝送線に故障が生じても伝送線の間には所定の電位が生じ、各多重ノード間のデータ伝送が可能になり、本発明を用いるシステム全体の多重伝送の信頼性を高めることができる。 Thus, in this embodiment, each multiplex node, cause the predetermined potential between the even transmission line failure occurs in the transmission line, enables the data transmission between the multiplex nodes, the entire system using the present invention it is possible to improve the reliability of the multiplex transmission.

(発明の効果) 以上説明したように、本発明では、共通の信号伝送線を介して相互に接続された少なくとも2つの多重ノードを有し、当該各多重ノードはいずれかの多重ノードの送信要求に応じて所定の送信データを送信する多重伝送方式において、前記信号伝送線は少なくとも3つの信号伝送線からなり、前記各多重ノードは該信号伝送線のうち少なくとも1つの信号伝送線の電圧を検知し、該電圧値に応じて各信号伝送線の状態を特定し、かつ、少なくとも1つの多重ノードは前記各多重ノードと通信して故障を検知した際には、前記信号伝送線の電圧を変化させて前記各信号伝送線の状態を変化させ、各多重ノード間のデータ伝送を行うので、伝送線上の故障が生じても各多重ノード間でデータ伝送を効率的に行うことができる。 As has been described (Effect of the Invention) In the present invention has at least two multiple nodes are connected to one another via a common signal transmission line, transmission request of the respective multiplex nodes either multinode detecting the multiplex transmission method for transmitting a predetermined transmission data, the signal transmission line comprises at least three signal transmission lines, a voltage of at least one signal transmission line of said each multiplex node the signal transmission line according to and, in response to the voltage value to identify the state of each signal transmission line, and at least one multiple nodes upon detecting a failure in communication with each of the multiplex nodes, it changes the voltage of the signal transmission line changing the state of each of the respective signal transmission lines by, since the data transmission between the multiplex nodes, data can be transmitted efficiently between the fault occurs even if the multiplex node of the transmission line.

【図面の簡単な説明】 BRIEF DESCRIPTION OF THE DRAWINGS

第1図は、本発明に係る多重伝送方式の構成を示す構成ブロック図、第2図は第1図に示した電圧検知回路の一実施例を示す回路図、第3図は同じく送信制御回路の一実施例を示す回路図、第4図は同じく受信制御回路の一実施例を示す回路図、第5図は同じく終端回路の一実施例を示す回路図、第6図は第1図に示した多重ノードによる信号線の故障処理の動作を説明するためのフローチャート、第7図は各伝送状態での伝送線の電位を示す図、第8図は受信制御回路の他の実施例を示す回路図、 Figure 1 is a block diagram showing a configuration of a multiplex transmission method according to the present invention, FIG. 2 is a circuit diagram showing an embodiment of a voltage detection circuit shown in FIG. 1, FIG. 3 is also the transmission control circuit circuit diagram showing an embodiment of FIG. 4 is also a circuit diagram showing an embodiment of a reception control circuit, the circuit diagram showing an embodiment of Fig. 5 likewise terminating circuit, Figure 6 in Figure 1 flowchart illustrating a multi-node operation failure processing of the signal lines by showing, FIG. 7 is a diagram showing the potential of the transmission line in each transmission state, FIG. 8 shows another embodiment of the reception control circuit circuit diagram,
第9図は多重ノードの他の実施例を示す構成ブロック図、第10図は従来の多重伝送方式の構成を示す構成ブロック図である。 Figure 9 is a block diagram showing another embodiment of a multi-node, FIG. 10 is a block diagram showing a structure of a conventional multiplex transmission method. 30,40,50,60……多重ノード、31,51,61,70……通信制御回路、32,52,62,72……送信制御回路、33,53,63,71…… 30, 40, 50, 60 ...... multiplex nodes, 31,51,61,70 ...... communication control circuit, 32,52,62,72 ...... transmission control circuit, 33,53,63,71 ......
受信制御回路、34,54,64……電圧検知回路、55,65…… Reception control circuit, 34,54,64 ...... voltage sensing circuit, 55 and 65 ......
終端回路、56……電圧発生回路、A,B,C……伝送線。 Termination circuit, 56 ...... voltage generating circuit, A, B, C ...... transmission line.

Claims (2)

    (57)【特許請求の範囲】 (57) [the claims]
  1. 【請求項1】共通の信号伝送線を介して相互に接続された少なくとも2つの多重ノードを有し、当該各多重ノードはいずれかの多重ノードの送信要求に応じて所定の送信データを送信する多重伝送方式において、前記信号伝送線は少なくとも3つの信号伝送線からなり、前記各多重ノードは該信号伝送線のうち少なくとも1つの信号伝送線の電圧を検知し、該電圧値に応じて各信号伝送線の状態を特定し、かつ、少なくとも1つの多重ノードは前記各多重ノードと通信して故障を検知した際には、前記信号伝送線の電圧を変化させて前記各信号伝送線の状態を変化させ、各多重ノード間のデータ伝送を行うことを特徴とする多重伝送方式。 [Claim 1 further comprising at least two multiplex nodes interconnected via a common signal transmission line, and transmits a predetermined transmission data in response to the transmission request of each multiplex node either multinode in multiplex transmission method, made from the signal transmission line at least three signal transmission lines, each multiplex node detects a voltage of at least one signal transmission line of the said signal transmission line, each signal in accordance with the voltage value to determine the status of the transmission line, and at least one multiple nodes upon detecting a failure in communication with each of the multiplex nodes, said varying the voltage of the signal transmission line the state of each signal transmission line varied, multiplex transmission method which is characterized in that the data transmission between the multiplex nodes.
  2. 【請求項2】前記各多重ノードは少なくとも3組の信号伝送線の対のうち、所定の信号伝送線の対の電位を受信する受信手段を有し、信号伝送線の故障により受信が不可能な際には、前記所定の信号伝送線の対を他の組合せに切り換えることを特徴とする請求項1記載の多重伝送方式。 Wherein said each multiplex node of the pair of the at least three sets of signal transmission lines, comprising a receiving means for receiving a potential of a given pair of signal transmission lines, impossible reception by the failure of the signal transmission line such a case, multiplex transmission method according to claim 1, wherein the switching the pair of said predetermined signal transmission lines to another combination.
JP2113751A 1990-04-27 1990-04-27 Multiplex transmission system Expired - Lifetime JP2851124B2 (en)

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JP2113751A JP2851124B2 (en) 1990-04-27 1990-04-27 Multiplex transmission system
CA 2041309 CA2041309A1 (en) 1990-04-27 1991-04-26 Multipath transmission system
DE1991631082 DE69131082D1 (en) 1990-04-27 1991-04-29 Multipath transmission system
EP19910303879 EP0454505B1 (en) 1990-04-27 1991-04-29 Multipath transmission system
DE1991631082 DE69131082T2 (en) 1990-04-27 1991-04-29 Multipath transmission system
US08/024,815 US5321689A (en) 1990-04-27 1993-03-01 Multipath transmission system

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EP0454505A2 (en) 1991-10-30
US5321689A (en) 1994-06-14

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